jeff_wisnia wrote:
dpb wrote:
....

A plug "broken"??? How? What broke? In 50 years w/ all personal
automobiles and light trucks plus tractors and other farm equipment BD
(before diesel) I've never seen a broken plug other than breaking the
insulation or somesuch external damage.

Well I have....

A few years ago my wife's 100K plus miles Oldsmobile had a tune up
including new plugs and plug leads. A few weeks later a noticable miss
developed and my mechanic found that one of the plugs he'd just replaced
had lost it's ground electrode. He replaced the plug "under warranty"
and her car seemed to be running OK after that.
....

Stuff _can_ happen but it surely isn't common.

If the electrode was gone when the plug came out, it likely was laying
on top of the cylinder. They should've gotten it out then rather than
just sticking another plug in and going on...

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